Sealed oil tank liquid level transmitter

[0030] Detailed ways,

[0031]A sealed oil tank liquid level transmitter, comprising a sensor shell 1, a main splint 2, an air outlet plate 3, a secondary splint 4, a circular hole 5 of the auxiliary splint, a vent pipe 6, a lead wire 9 on the sensor, a wire protection pipe 14, Flange 17. The sensor is fixed in the sensor housing 1, the lower end of the vent pipe 6 is fastened on the air outlet plate 3, and the upper end extends above the measuring liquid level. The flange 17 is connected, and the lead wire 9 on the sensor is led out through the conduit 14 . The sensor is a differential pressure sensor. The pressure sensing surfaces on both sides of the differential pressure sensor sense the air pressure above the measured liquid surface and the pressure at the measured liquid level point in the liquid medium. The differential pressure reflects the liquid level height. In order to improve the liquid level transmitter Anti-interference ability and adapt to long-distance signal transmission.

[0032] Example: The linear adjustment, zero point adjustment, full scale adjustment, and temperature compensation adjustment circuits of the pressure-sensitive element are integrated on the pressure-sensitive element through the integration technology of signal processing circuits such as thick-film hybrid integrated circuits or flexible circuit board integration. Integrated, so that the output of the sensor lead wire 9 is a standard current or voltage signal, and a long-distance transmission of the signal of a sealed oil tank liquid level transmitter is realized.

[0033] The sensor housing 1 is a rectangular cavity structure composed of a main plate 2 and a sub-clamp 4. The outer hexagonal screw 18a is used as a positioning member to clamp and fix the sensor, and is compacted and sealed with a sealing ring 7, and the pressure sensing on both sides of the sensor is exposed. surface to protect the sensor components and make the sensor feel differential pressure. The main splint 2 is connected with an air outlet plate 3 and a ventilation pipe 6, the air outlet plate 3 is provided with a through hole that makes the pressure sensing surface of the low pressure chamber of the sensor airtightly communicated with the outside world, and the air outlet plate 3 is tightly and tightly connected with the through hole on the ventilation pipe 6, The lower end of the vent pipe 6 is threadedly fastened on the air outlet plate 3, and the upper end extends above the measuring liquid level to sense the vapor pressure of the liquid level in the sealed oil tank, that is, the upper air pressure.

[0034] The auxiliary splint 4 is a hollow flat plate with a circular hole 5 in the center that communicates with the outside world. The liquid to be tested directly contacts the pressure-sensitive surface of the high-pressure chamber of the sensor through the circular hole 5 on the side of the auxiliary splint 4, and the sensor feels on the side of the auxiliary splint. The pressure at the point of the measured liquid level in the liquid medium.

[0035] The lower end of the grommet 14 is connected with the sensor housing 1 through the sealing joint 8, and is reinforced with the hexagonal nut 11 and the welding sleeve 13, and the sealing cone 10, the compression ring 12 and the sealing ring 7 are compacted and tightly sealed. The upper end of the grommet 14 is connected to the flange 17 through the combined components of the coupling sleeve 15, the hexagonal nut 11 and the flange joint 16, and the differential pressure signal of the sensor is output through the sensor lead 9 in the grommet 14. , the length of the protection pipe 14 and the ventilation pipe 6 is 1m to 20m, which is determined according to the depth of the oil tank. The flange 17 can be fixed on the casing of the oil storage tank by the hexagon screws 18 and the sealing ring 7 to form a sealed oil tank cavity.

[0036] In the present invention, all process connections are sealed with high-temperature and corrosion-resistant sealing rings, so that the transmitter can maintain its tightness and reliability under long-term high temperature, high static pressure, and corrosive medium working conditions.